A number of patients suffer from vascular occlusions. Vascular occlusions can occur in the coronary arteries as well as in peripheral arteries such as those found in a patient's legs. Occlusions can be partial occlusions that reduce blood flow through the occluded portion of an artery. Occlusions can also be total occlusions, which substantially reduce or even completely eliminate blood flow through the occluded portion of the artery. Total occlusions such as chronic total occlusions can be difficult to traverse with existing catheters and guidewires, as they can include stiff or tough portions at their proximal and distal limits.
Physicians have attempted to cross or recanalize chronically totally occluded blood vessels such as arteries using a variety of devices and techniques. Unfortunately, many of these devices and techniques have relatively low success rates and relatively high rates of complications. A particular issue is penetrating a proximal cap of an occlusion without damaging the surrounding blood vessel, as proximal caps can have a curved or angled configuration that guides devices into the vessel wall or perhaps into a branch vessel.
Therefore, a need remains for a safe and effective way to penetrate and traverse occlusions such as chronic total occlusions. A need remains for a safe and effective way to penetrate and traverse difficult portions of an occlusion such as a proximal cap, which then allows traversing of the remainder of the occlusion with a conventional guidewire, catheter or other device.